We break up the world into concepts and labels in our everyday functioning. When we walk down the street, we label the car as a car. We cross someone on the street and label them as a woman and it’s associations. Attractive. Caucasian. Tall.. etc.
When we do this labeling, and conceptualization, we subtly create a duality between our self and other. Patients who have lesions in the back part of the brain called the association cortex are not able to distinguish between self and other. One patient with that lesion was not able to point to any items outside his own body.
There are different types of space; physical, psychological, and mental space. The sense of space can also go away which results in a substrate space. There is also non-dual space where the subject and object collapse.
Previc1)http://www.ncbi.nlm.nih.gov/pubmed/16439158 describes 4 levels of physical space:
- Peripersonal – space within 6.5 ft of our body. The posterior inferior parietal region.
- Extrapersonal focal – representation of objects above the horizontal plane and recognizes faces at distances beyond 6.5 ft. Inferotemporal region.
- Extrapersonal action – system that allows us to navigate. Superior and medial temporal regions.
- Extrapersonal ambient – orients us in space. Parietooccipital region.
The occipital to temporal pathway controls the WHAT. The occipital to parietal pathway controls the WHERE. The posterior parietal cortex and the posterior superior temporal sulcus are usually engaged in exercises where you have to point out objects in space. Allocentric space is the space of the objects we represent outside ourselves. This is contrasted with an egocentric frame of reference which is how we represent objects in the world with us in the center.
Very clever experiments have been conducted in the virtual reality space. Space gets distorted in the virtual world. We can still identify with our arm even if it is lengthen to twice it’s length.
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